docs: def _calculate_unique_id(self, xblock):
          """
          Provide a default value for fields with `default=UNIQUE_ID`.
  
          Returned string is a SHA1 hex digest that is deterministically calculated
          for the field in its given scope.
          """
          key = scope_key(self, xblock)
          return hashlib.sha1(key.encode('utf-8')).hexdigest()